A red BMW 330, a black BMW X5 and a red Kia Rio were all involved in the accident and police are appealing for witness who may have witnessed it to come forward.

A police car blocking the A505 near Royston after a crash on March 13 (Image: @EHertsRuralPolice)

Sergeant Steve Andrews from the Bedfordshire, Cambridgeshire and Hertfordshire Road Policing Unit said: “I am appealing for anyone who witnessed the incident, or events leading up to it, to please get in touch.